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Boreal ecosystems are experiencing extensive changes because of anthropogenic stressors such as climate change. Information on density of species at multiple sites is vital to understand and manage the impact of these changing conditions on boreal forest communities. Yet, for most boreal forest species, including the vast majority of mammals, obtaining reliable estimates of density is exceedingly difficult. Recently developed methods for the estimation of densities of unmarked animals from camera-trapping data could help to overcome this hurdle, but have not yet been empirically validated in many ecosystems. Here, we assess the ability of camera traps to estimate density of snowshoe hare (Lepus americanus) using three different models: the random encounter model (REM), the random encounter and staying time (REST) model, and the time-to-event (TTE) model. We additionally evaluate the relationship between hare density and two simple indices based on camera detection rate and pellet counts. Across 13 sites in North Central Washington, United States, we compared live-trapping spatially explicit capture–recapture (SECR) estimates of density to the three camera-based density models and the two indices. We found that the camera-based models, in particular the REM and REST models, performed well in estimating densities consistent with the live-trapping data, with an average difference in density from SECR-based estimates of only 0.12 and 0.13 hares/ha, respectively. Both indices also had strong predictive relationships with hare density. Our results show that, owing to their noninvasive nature and relative ease of application, camera-based methods could be used to obtain hare density estimates at much larger spatiotemporal scales than have been applied to date. Given the keystone role of hare in boreal ecosystems, and emerging evidence of hare range retraction, the ability to estimate densities across many sites is a key tool for hare conservation and management. Moreover, our results are highly encouraging for the application of camera-based methods to obtain density estimates on a wide variety of boreal forest species, though additional validation will be necessary.

Congeneric species often share ecological niche space resulting in competitive interactions that either limit co-occurrence or lead to niche partitioning. Differences in fundamental nutritional niches mediated through character displacement or isolation during evolution are potential mechanisms that could explain overlapping distribution patterns of congenerics. We directly compared nutritional requirements and tolerances that influence the fundamental niche of mule (Odocoileus hemionus) and white-tailed deer (O. virginianus), which occur in allopatry and sympatry in similar realized ecological niches across their ranges in North America. Digestible energy and protein requirements and tolerances for plant fiber and plant secondary metabolites (PSMs) of both deer species were quantified using in vivo digestion and intake tolerance trials with six diets ranging in content of fiber, protein, and PSMs using tractable deer raised under identical conditions in captivity. We found that compared with white-tailed deer, mule deer required 54% less digestible protein and 21% less digestible energy intake per day to maintain body mass and nitrogen balance. In addition, they had higher fiber, energy, and dry matter digestibility and produced glucuronic acid (a byproduct of PSM detoxification) at a slower rate when consuming the monoterpene α-pinene. The mule deers’ enhanced physiological abilities to cope with low-quality, chemically defended forages relative to white-tailed deer might minimize potential competitive interactions in shared landscapes and provide a modest advantage to mule deer in habitats dominated by low-quality forages.

The application of species distribution models (SDMs) to areas outside of where a model was created allows informed decisions across large spatial scales, yet transferability remains a challenge in ecological modeling. We examined how regional variation in animal‐environment relationships influenced model transferability for Canada lynx (Lynx canadensis), with an additional conservation aim of modeling lynx habitat across the northwestern United States. Simultaneously, we explored the effect of sample size from GPS data on SDM model performance and transferability. We used data from three geographically distinct Canada lynx populations in Washington (n = 17 individuals), Montana (n = 66), and Wyoming (n = 10) from 1996 to 2015. We assessed regional variation in lynx‐environment relationships between these three populations using principal components analysis (PCA). We used ensemble modeling to develop SDMs for each population and all populations combined and assessed model prediction and transferability for each model scenario using withheld data and an extensive independent dataset (n = 650). Finally, we examined GPS data efficiency by testing models created with sample sizes of 5%–100% of the original datasets. PCA results indicated some differences in environmental characteristics between populations; models created from individual populations showed differential transferability based on the populations' similarity in PCA space. Despite population differences, a single model created from all populations performed as well, or better, than each individual population. Model performance was mostly insensitive to GPS sample size, with a plateau in predictive ability reached at ~30% of the total GPS dataset when initial sample size was large. Based on these results, we generated well‐validated spatial predictions of Canada lynx distribution across a large portion of the species' southern range, with precipitation and temperature the primary environmental predictors in the model. We also demonstrated substantial redundancy in our large GPS dataset, with predictive performance insensitive to sample sizes above 30% of the original., Using a collaborative dataset from three populations of Canada lynx in the northwestern United States, we explore the impact of regional variation in animal‐environment relationships on model transferability, as well as how model performance and transferability is affected by the size of the GPS dataset used. Despite the specialist nature of Canada lynx, we found regional differences in lynx‐environment relationships. Model transferability improved as populations became closer in terms of their lynx‐environment relationships. We found substantial redundancy in our large GPS dataset, with predictive performance insensitive to sample sizes above 30% of the original.

The amount and composition of phytochemicals in forage plants influences habitat quality for wild herbivores. However, evaluating forage quality at fine resolutions across broad spatial extents (i.e., foodscapes) is challenging. Unmanned aerial systems (UAS) provide an avenue for bridging this gap in spatial scale. We evaluated the potential for UAS technology to accurately predict nutritional quality of sagebrush (Artemisia spp.) across landscapes. We mapped seasonal forage quality across two sites in Idaho, USA, with different mixtures of species but similar structural morphotypes of sagebrush. We classified the sagebrush at both study sites using structural features of shrubs with object-based image analysis and machine learning and linked this classification to field measurements of phytochemicals to interpolate a foodscape for each phytochemical with regression kriging. We compared fine-scale landscape patterns of phytochemicals between sites and seasons. Classification accuracy for morphotypes was high at both study sites (81–87%). Forage quality was highly variable both within and among sagebrush morphotypes. Coumarins were the most accurately mapped (r2 = 0.57–0.81), whereas monoterpenes were the most variable and least explained. Patches with higher crude protein were larger and more connected in summer than in winter. UAS allowed for a rapid collection of imagery for mapping foodscapes based on the phytochemical composition of sagebrush at fine scales but relatively broad extents. However, results suggest that a more advanced sensor (e.g., hyperspectral camera) is needed to map mixed species of sagebrush or to directly measure forage quality.

We present a reply to a recent article in Ecology and Evolution ("Measuring agreement among experts in classifying camera images of similar species" by Gooliaff and Hodges) that demonstrated a lack of consistency in expert-based classification of images of similar-looking species. We disagree with several conclusions from the study, and show that with some training, and use of multiple images that is becoming standard practice in camera-trapping studies, even nonexperts can identify similar sympatric species with high consistency.

The persistence of cold-adapted species along their equatorial range edge (i.e., southern range edge for species in the Northern Hemisphere and northern range edge for species in the Southern Hemisphere) is threatened by climate change. These species will be challenged not just by unfavorable climatic regimes, but also by changing biotic interactions, which may be more intense along equatorial edges. However, we currently have a poor understanding of the nature of biotic interactions at range edges and how climate may mediate those interactions, particularly for cold-adapted mammals. We studied the distribution of threatened Canada lynx (Lynx canadensis) at their southern range edge in northern Washington, United States from 2014 to 2016. Using data collected from 397 camera-trap stations in snow-on and snow-off seasons, and single- and 2-species occupancy models, we investigated seasonal patterns of habitat selection and spatial association of lynx with their primary prey (snowshoe hares, Lepus americanus) and potential competitors (bobcats, Lynx rufus; cougars, Puma concolor). Single-species occupancy models revealed lynx distribution was strongly associated with snowshoe hare abundance and topographic variables related to lower temperatures and increased moisture. In contrast, bobcats and cougars were more generalized in their habitat associations or displayed the reverse response to environmental variables. Spatial overlap of the 3 felid species increased during snow-off seasons. Two-species occupancy models showed a decrease in use of camera sites by lynx when bobcats were present, suggesting lynx were avoiding their warm-adapted competitor. Taken together, these results suggest that biotic interactions are partly shaping large-scale lynx distribution patterns along their southern range edge. Increasing temperatures and loss of snow may result in a combination of habitat isolation and potential for increased competitive interactions for lynx at the margins of their range.

Landscape-scale predictions of species abundance or density are of fundamental importance to conservation and management of ecosystems. Yet, developing these models remains challenging, as they require linking broad-scale population data with habitat characteristics that influence species abundance. Advances in remote sensing technology have resulted in increased availability of spatially continuous, high-resolution data that relate to ecologically important habitat characteristics. In forested systems, Light Detection and Ranging (LiDAR) and Digital Arial Photogrammetry (DAP) are of particular interest owing to their ability to estimate vegetative structure that drives variability in abundance or density of some forest-dependent species. We used an extensive dataset on the density of a keystone boreal forest species, the snowshoe hare (Lepus americanus) in northcentral Washington, USA, to examine which LiDAR- and DAP-derived habitat variables most strongly influence snowshoe hare density, and projected these relationships across the landscape to derive a hare density surface for our 53 km2 study area. We found snowshoe hare density is most influenced by habitat variables related to tree height (a proxy for stand age), horizontal cover, and vertical cover, and our model had high predictive performance on a spatially-independent validation dataset. Hare densities increased as horizontal cover and canopy cover increased, with our highest hare densities occurring in areas with >9% horizontal cover (% of LiDAR returns in 1–4 m height stratum), >65% canopy cover and tree height (a proxy for stand age) of ~5–10 m. To demonstrate the management implications of this work, we show that our landscape-scale model of predicted hare density helps understand habitat use by threatened Canada lynx (Lynx canadensis), a primary predator of hare. Our results show how coupling population data with remotely sensed forest structure metrics allows for continuous, large-scale population estimates. Such integration provides an important management tool for examining spatiotemporal changes in populations as boreal ecosystems come under increasing stress from climate and land use change.

Large mammalian herbivores are experiencing population reductions and range declines. However, we lack regional knowledge of population status for many herbivores, particularly in developing countries. Addressing this knowledge gap is key to implementing tailored conservation strategies for species whose population declines are highly variable across their range. White-lipped peccaries (Tayassu pecari) are important ecosystem engineers in Neotropical forests and are highly sensitive to human disturbance. Despite maintaining a wide distributional range, white-lipped peccaries are experiencing substantial population declines in some portions of their range. We examined the regional distribution and population status of the species in Mesoamerica. We used a combination of techniques, including expert-based mapping and assessment of population status, and data-driven distribution modelling techniques to determine the status and range limits of white-lipped peccaries. Our analysis revealed declining and highly isolated populations of peccaries across Mesoamerica, with a range reduction of 87% from historic distribution and 63% from current IUCN range estimates for the region. White-lipped peccary distribution is affected by indices of human influence and forest cover, and more restricted than other sympatric large herbivores, with their largest populations confined to transboundary reserves. To conserve white-lipped peccaries in Mesoamerica, transboundary efforts will be needed that focus on both forest conservation and hunting management, increased cross-border coordination, and reconsideration of country and regional conservation priorities. Our methodology to detail regional white-lipped peccary status could be employed on other poorly-known large mammals. Universidad Nacional, Costa Rica El Colegio de la Frontera Sur, México Wildlife Conservation Society, United States Instituto Internacional en Conservación y Manejo de Vida Silvestre

The impact of extensive changes in land use and climate on species has led to an increasing focus on large-scale conservation planning. However, these plans are often static conservation prescriptions set against a backdrop of rapidly changing environments, which suggests that large-scale information on threats can improve the functionality of planning efforts. Jaguars (Panthera onca) are the focus of a range-wide conservation strategy extending from Mexico to Argentina that consists of jaguar conservation units (JCUs) and modeled corridors. Recent deforestation is a major threat to jaguar populations, but forest loss has not been systematically assessed across the entire jaguar network. In this study, we quantified the amount and rate of deforestation in JCUs and corridors between 2000 and 2012. JCUs lost 37,780 km2 forest (0.93%) at an increasing rate of 149.2 km2 yr−2, corridors lost 45,979 km2 (4.43%) at a decreasing rate of 40.1 km2 yr−2, and levels of forest fragmentation increased in corridors. Protected sections of JCUs and corridors lost less forest than unprotected sections, suggesting efforts to increase protected status of jaguar conservation areas are warranted. Higher deforestation in corridors indicates difficulties in maintaining connectivity of jaguar populations, and suggests the need for increased engagement with communities within corridor landscapes. Assessment of spatial variability of anthropogenic threats within the jaguar network may improve jaguar conservation by informing network prioritization and function.

De-extinction is becoming potentially feasible for restoring extinct species in the wild, but research is required to determine the likelihood of success in light of contemporary and future environmental change. We assessed 1900–2100 change in suitable climate and land cover in the historic range of Carolina parakeet (Conuropsis carolinensis), ivory-billed woodpecker (Campephilus principalis) and passenger pigeon (Ectopistes migratorius), in North America. Parakeet and woodpecker historic range currently remains climatically-favourable, but intensified land use has broadly reduced habitat in contemporary landscapes. For passenger pigeon, more substantive loss in climate and land cover suitability exists in both the historic full range and primary breeding range. Long-term climate and land cover projections suggest that improved habitat suitability and increased potential future distribution outside historic ranges are likely for each de-extinction candidate. While such changes could improve probability of success for de-extinction programs, extensive mismatch between historic and future habitat suitability highlights the potential risks of reviving species that may colonize novel geographic space. To date, potential long-term negative effects of de-extinction programs to ecosystems outside historic ranges have not been elucidated, making this a priority concern for any serious proposal. To address whether benefits of reinstating extinct species to historic ecosystems outweigh risks to extant species outside their historic range will require extensive ecological, social and economic analyses that extend beyond that conducted to-date for this potentially transformational conservation tool.

Large-scale conservation planning entails the establishment of protected area networks that retain substantive natural habitat, biodiversity, and functional connectivity, but developing such networks at the spatial extent needed for meeting global targets involves considerable logistical, political, and social challenges. Normally, governments oversee development of protected area networks, but in the absence of political leadership private initiatives may offer a reasonable alternative approach in conservation planning. We review the Canadian Boreal Forest Agreement (CBFA), a private conservation planning initiative established by forestry companies and environmental organizations that suspends permitted logging activities on roughly 29 million hectares of boreal forest in Canada. The CBFA is touted as a milestone in conservation planning, multi-stakeholder cooperation, and woodland caribou conservation. Yet, the CBFA: 1) involves public land but excludes federal, provincial and aboriginal governments; 2) is not legally binding or necessarily transferrable upon sale of forest tenures; and 3) exempts industrial activities other than logging. Covering 4.6% of the boreal region of Canada, CBFA land tenures do not include most boreal ecozones and do not conform to standard guidelines for designing effective protected area networks. Further, the CBFA does not anticipate effects of climate change, which by 2080 likely will render land tenures unsuitable for caribou, the flagship species of the agreement. We conclude that private initiatives like the CBFA may constitute positive, initial steps toward large-scale conservation planning, but their successful integration into protected area networks will require scientifically robust and transparent efforts that are more fully coordinated with public initiatives.

Identifying the ecological and life-history traits that render species vulnerable to fragmentation is an important prerequisite for the development of effective conservation strategies to minimize future biodiversity losses. When determining how species traits influence vulnerability to fragmentation, however, several important confounding factors such as detectability and synergistic effects among traits are rarely considered. In this study, after controlling for these methodological shortcomings, we determined how species traits influenced fragmentation vulnerability using bird data collected from islands created by the inundation of the Thousand Island Lake, China. We obtained eight species traits from field surveys and from the literature: natural abundance, geographical range size, habitat specificity, body size, trophic level, mobility, fecundity, and nest type. After phylogenetic correction, these traits were used separately and in combination to assess their associations with the index of fragmentation vulnerability, the proportion of islands occupied. Inclusion of detectability in analysis resulted in considerable increases in overall island occupancy for all species in general and for cryptic species in particular. Accounting for detectability altered the rank of best models and thus influenced the identification of the relationships between species traits and fragmentation vulnerability. We found synergistic interactions between natural abundance and habitat specificity. Our findings highlight the importance of incorporating detectability and synergistic effects among traits into future studies. From a conservation perspective, our results suggest that we should give priority conservation efforts to rare species with low natural abundance and high habitat specificity.

International political boundaries challenge species conservation because they can hinder coordinated management. Peripheral transboundary species, those with a large portion of their range in one country and a small, peripheral portion in an adjacent country, may be particularly vulnerable to mismatches in management because peripheral populations are likely in greater conservation need than core populations. However, no systematic assessment of peripheral transboundary species or their status across borders has been attempted. We show that numerous species in three vertebrate taxa qualify as peripheral transboundary species in North America, and that these species are often protected differently across US–Canadian and US–Mexican borders. Asymmetries in cross‐border protection may threaten populations through disruption of connectivity between periphery and core regions and are especially relevant given expected impacts of climate change and the US–Mexico border wall. Our results highlight the need for greater international collaboration in management and planning decisions for transboundary species.

The potential conservation value of fragmented or countryside landscapes in the tropics is being increasingly recognized. However, the degree to which fragmented landscapes can support species and the key patch and landscape features that promote population persistence remain poorly understood for elusive species such as ground-dwelling birds. We examined the presence/absence of seven species of galliforms and tinamous in 50 forest patches of 2.9–445 ha in northern Guatemala using camera traps and audiovisual surveying. After accounting for differences in detectability among species we found great variation in patterns of vulnerability of these species to habitat loss and fragmentation, with the three largest species being the most vulnerable. Distribution patterns of species among patches was influenced more strongly by measures of landscape context, such as the amount and configuration of habitat in the surrounding landscape, than within-patch variation in vegetation structure or disturbance. Our results indicate that large-bodied game birds may be particularly sensitive to habitat loss and fragmentation and emphasize that management efforts for these species need to go beyond consideration of local, within-patch factors to consider the impact of processes in the surrounding landscape. Our findings also demonstrate the utility of camera traps as a methodology for surveying large terrestrial bird species in fragmented landscapes.

Maintaining forest biodiversity requires an understanding of how forest-dependent species respond to a variety of forestry activities. This is particularly true for mammals, which often act as keystone species or focal species for conservation efforts in forest ecosystems. Snowshoe hares ( Lepus americanus ) serve as an important herbivore and prey resource throughout their range in the boreal forest. We examined the response of hares to partial and clearcut harvest, site preparation activities (post-harvest burning or chemical/mechanical preparation for regrowth), and precommercial thinning, using pellet plots on 359 forest stands across an expansive landscape in northern Idaho over a 5-year period. Hares initially responded negatively to harvest, with clearcut harvest having a greater negative impact than partial harvest, and this response was exacerbated by site preparation activities. Mid-successional stands (15–40 years old) that had been clear cut with site preparation treatments applied or partially harvested with no site preparations applied had greater snowshoe hare pellet counts than mature or recently harvested stands. Pre-commercial thinning had no detectable effect on hares in this landscape. Our findings suggest an interaction between site preparation and type of harvest (clear-cut vs. partial), which suggests that both the initial negative impacts and subsequent positive response to site preparation as stands age are attenuated somewhat in partially harvested vs. clear-cut stands. Our results likely relate to the influence of management activities on vegetative cover, which is strongly related to hare abundance in a variety of systems. They suggest that silvicultural activities such as site preparation could be damaging to hare populations when applied widely across landscapes, particularly when young age classes predominate. However, because the effects of harvest and site preparation are largely transitory, use of these techniques may not substantially depress hare populations if enough stands can be maintained in the 15–40 year age class.

Understanding the influence of large and small-scale heterogeneity on species distribution and abundance is one of the major foci of landscape ecology research in fragmented environments. Although a large number of studies have addressed this issue individually, little effort has been made to synthesize the vast amount of literature published in the last decade. We reviewed 122 focal patch studies on 954 species published between 1998 and 2009 to determine the probability of species responding significantly to landscape, patch, and within-patch variables. We assessed the influence of taxonomic, life history, and methodological variables on probability of response to these 3 levels. Species in diverse taxa responded at high rates to factors at all three levels, suggesting that a multi-level approach is often necessary for understanding species response in patchy systems. Mammals responded at particularly high rates to landscape variables and therefore may benefit more than other taxa from landscape-level conservation efforts in fragmented environments. The probability of detecting a species response to landscape context, patch, and within-patch factors was influenced by a variety of methodological aspects of the studies such as type of landscape metric used, type of response variable, and sample size. Study design issues rarely are discussed by authors as reasons why a particular study did not find an effect of a variable, but should be given more consideration in future studies.

The coyote (Canis latrans) has recently expanded its geographic range into Florida, and the impacts of this range expansion on Florida ecosystems are likely to be complex. An area of particular concern is the effect on native carnivores. From May 2001 to May 2002, we investigated the ecological relationships between the coyote and bobcat (Lynx rufus) in south-central Florida to determine how they partition space, habitat, time, and food. Ecological separation was facilitated by dietary differences. Coyotes preyed primarily upon large ungulates and consumed substantial quantities of fruit, whereas bobcats primarily consumed rodents and lagomorphs. Coyotes and bobcats displayed similar habitat selection and activity patterns, and their high interspecific overlap in home ranges indicated a lack of large-scale spatial segregation. However, at the finer scale of core areas, patterns of spatial segregation were present. The lack of evidence for negative interactions at our study site suggests that non-overlapping core areas reduces agonistic encounters between the 2 species.

Olfactory communication among mammals remains poorly studied yet may be key to understanding their ecology. This is particularly true for mammalian carnivores, which rely extensively on scent marking for communication. Previous research suggests that carnivore latrines play a large role in both intra- and interspecific communication. Despite the apparent complexity of mammal use of latrines, little work has examined behavior patterns of species that visit latrines. We used motion-triggered video cameras to study use and behavior of mammals at ocelot ( Leopardus pardalis ) latrines in Costa Rica. We documented temporal patterns of use by the focal species (ocelots), diversity of mammalian species using latrines, and behaviors that occurred at these sites. Ocelots showed peaks in visitation every 60–67 days and a shorter gap between intersexual versus intrasexual visits, supporting the idea that ocelot latrines are used to communicate information about reproductive status. Fourteen terrestrial mammal species visited the latrines, and these species engaged in a variety of behaviors, including mark investigation, scent marking, and acceptance of scent marks. The complexity and frequency of behaviors by nonfocal species suggest that latrines may play as important a role in communication for these other species as they do for ocelots. La comunicacion olfativa entre mamiferos ha sido poco estudiada, sin embargo puede ser la clave para el entendimiento de su ecologia. Esto es particularmente cierto para mamiferos carnivoros quienes dependen extensivamente de el marcaje de rastros olfativos para su comunicacion. Estudios previos siguieren que las letrinas juegan un rol importante en la comunicacion intra- e inter-especifica. A pesar de la aparente complejidad del uso de letrinas por parte de mamiferos, pocos trabajos han examinado los patrones de comportamiento de las especies que las visitan. Utilizamos camaras de videos sensibles al movimiento para estudiar el uso y comportamiento de mamiferos en letrinas de ocelotes ( Leopardus pardalis ) en Costa Rica. Documentamos los patrones de uso temporal por parte de especies focales (ocelotes), la diversidad de especies de mamiferos y los comportamientos que ocurrieron en estos lugares. Los resultados indican que el uso por parte de los ocelotes muestran picos de visitas cada 60 a 67 dias y un intervalo mas corto para visitas inter-sexuales que para visitas intra-sexuales. Esto apoya la idea de que las letrinas de los ocelotes son utilizadas para comunicar estatus reproductivos. Un total de catorce mamiferos terrestres visitaron las letrinas y estas especies mostraron una variedad de comportamientos, incluyendo investigacion, marcaje y aceptacion de rastros olfativos. La complejidad y frecuencia de comportamientos por especies no focales, sugieren que las letrinas pueden jugar un rol importante en la comunicacion de otras especies como lo es para los ocelotes.

Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer) accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose) and Rangifer tarandus (caribou), in North America. We used MaxEnt models to predict the recent (2000) and future (2050) ranges (probabilities of occurrence) of the cervids and a parasite Parelaphostrongylus tenuis (brainworm) taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces / R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces / R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces / R. tarandus are likely to decline, but minimal spatial overlap where A. alces / R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.